1. Field of the Invention
The present invention relates in general to an accelerator pedal assembly for use in a motor vehicle, and more particularly to an accelerator pedal assembly which has a damping mass (or weight) to prevent the accelerator pedal assembly from resonating with the vibration of a vehicular engine.
2. Description of the Prior Art
In order to clarify the task of the present invention, one conventional accelerator pedal assembly of the type equipped with a damping mess will be outlined with reference to FIG. 2 of the accompanying drawings.
The accelerator pedal assemblies of this type are described in Japanese Utility Model First Provisional Publications Nos. 56-40022 and 68-40023.
The accelerator pedal assembly shown in FIG. 2 comprises an elongate pivotal lever (or member) 1 which is pivotally supported as is generally middle portion (no numeral) by a pivot shaft 2. The lever 1 has thus upper and lower portions (no numerals) which are bounded by the pivoted middle portion. The lever 1 is so shaped or curved as not to interfere with other members located near the lever 1. A accelerator pedal 3 is secured to the lower portion of the lever 1, onto which a foot of a driver is adapted to put. The lever 1 has at the upper portion a semicircular recess 6 to which an accelerator cable 4 is connected. The cable 4 leads to a known mechanism for operating fuel supply means of the engine. Although not shown in the drawing, a spring is associated with the pivot shaft 2 to bias the lever 1 in a direction to raise the pedal 3.
In order to prevent the accelerator pedal assembly from resonating with the vibration of the engine, the lever 1 is equipped at the leading end of the upper Portion thereof with a damping mass 5 whose center of gravity is designated by reference "G".
When, thus, the pedal 3 is depressed by the driver against the biasing force of the spring, the lever 1 is pivoted about a pivot axis 12 in a direction to pull the accelerator cable 4. With this, the known mechanism of the fuel supply means is actuated.
However, hitherto, the positioning of the damping mass 5 for such an accelerator pedal assembly has been given little thought.
In fact, as is seen from FIG. 2, hitherto, the damping mass 6 (more specifically, the center G of gravity of the damping mass 5) is positioned away by a distance of "L" from an imaginary straight line "L" which passes through both points "P" and "Q", the point "P" being the center of the pivoted middle portion of the level 1, and the point "Q" being the center of the semicircular recess S.
This arrangement however induces the following drawback.
That is, when the pedal 3 is depressed, a considerable torsional stress is produced in the lever 1 due to a certain moment produced around the line "L", which moment is the product of an inertial force of the damping mass and the distance "L". This phenomenon however give the driver uncomfortable pedal feed and lowers the durability of the accelerator pedal assembly.